what do we mean by grade of concrete.?
Concrete grades are denoted by M10, M20, M30 according to their compressive strength.
The “M” denotes Mix design of concrete followed by the compressive strength number in N/mm2
“Mix” is the respective ingredient proportions which are Cement: Sand: Aggregate Or Cement: Fine Aggregate: Coarse Aggregate.
If we mention M10 concrete, it means that the concrete has 10 N/mm2 characteristic compressive strength at 28 days.
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